CAJ | 학술논문

目的：确定电子射野影像系统（EPID）对头颈部放疗患者位置误差的修正效果。方法应用EPID对40例头颈部放疗患者的摆位误差进行测定分析。初次治疗前和以后每两周通过兆伏级EPID对患者治疗位置采集正交位射野验证影像，并与治疗计划中通过定位CT生成的数字重建射野（DRR）影像进行比对，医生认可比对结果后，记录下各方向摆位误差值。结果患者在x轴、y轴、z轴（x轴、y轴、z轴分别表示患者左右、前后和头脚方向）上的误差（系统误差±随机误差）分别为（0.7±1.33）mm，（0.28±1.74）mm，（0.13±1.29）mm；EPID验证结果和kV-CBCT验证结果在y轴、z轴方向无显著差异（P=0.859），在x轴方向有显著差异（P=0.000）。结论在头颈部放疗时，EPID系统可以修正患者的位置误差。
목적：학정전자사야영상계통（EPID）대두경부방료환자위치오차적수정효과。방법응용EPID대40례두경부방료환자적파위오차진행측정분석。초차치료전화이후매량주통과조복급EPID대환자치료위치채집정교위사야험증영상，병여치료계화중통과정위CT생성적수자중건사야（DRR）영상진행비대，의생인가비대결과후，기록하각방향파위오차치。결과환자재x축、y축、z축（x축、y축、z축분별표시환자좌우、전후화두각방향）상적오차（계통오차±수궤오차）분별위（0.7±1.33）mm，（0.28±1.74）mm，（0.13±1.29）mm；EPID험증결과화kV-CBCT험증결과재y축、z축방향무현저차이（P=0.859），재x축방향유현저차이（P=0.000）。결론재두경부방료시，EPID계통가이수정환자적위치오차。
Objective To explore the effect of electronic portal imaging device (EPID) in the correction of set-up errors in the radiotherapy of patients with head and neck cancer.Methods The set up errors in the radiotherapy of 40 patients with head and neck cancer were measured and analyzed with EPID. Portal images of orthogonal radiation ifelds located at the therapy positions of patients were collected by MV EPID before radiotherapy and every two weeks after radiotherapy. Then the portal images were compared with digital reconstructed radiography (DRR) images generated by CT positioning. Based on the recognition of the doctor on the comparison results, the set-up errors in various directions were recorded.Results The set-up errors in x axis、y axis and z axis were (0.7±1.33) mm, (0.28±1.74) mm and (0.13±1.29) mm, respectively. There was no signiifcant difference between veriifcation results of EPID and those of kV-CBCT in terms of set-up errors in y axis and z axis (P=0.859) while there were signiifcant differences between veriifcation results of EPID and those of kV-CBCT in terms of set-up errors in x axis (P=0.000).Conclusion EPID can effectively correct the set-up errors in the radiotherapy for head and neck cancer.